Dry cleaning system



March 10, 1953 E. A. CRESWICK 2,530,694

DRY CLEANING SYSTEM Filed Feb. 16, 1949 INVENTOR EDWARD A. CRESWICK AT TORNEYS Patented Mar. 10, 1953 UNITED STATES PATENT OFFICE DRY CLEANING SYSTEM Application February 16, 1949, Serial No. 76,676

12 Claims.

This invention relates to dry cleaning systems, such as are used for dry cleaning outer garments or other articles of wearing apparel, textile fabrics or the like. 7

One object of the invention is to provide an improved dry cleaning system, and method of operation thereof, which utilizes two baths, one for washing and the other for rinsing, with continuous filtering of both baths, and which twobath system and method combines the best features of the single-bath continuous filtration system and the batch system, while eliminating limitations and drawbacks of both thereof.

Operation of the well known single bath continuous filtration system involves the inherent limitation that a concentration of soap or other detergent sufficient to produce maximum cleaning action cannot be used in the petroleum or other solvent, since to do so would leave too much residual soap or other detergent in the fabric undergoing treatment. This has led to the use of moisture in excess, with attendant risks of shrinkage, to pro-spotting, and to the use of batch operation where good detergency is desired.

On the other hand, batch operation, while resulting in better cleansing, has other drawbacks. It requires considerable rinsing to rid the fabric of the high soap concentration, thus contaminating large volumes of solvent, consuming considerable soap or other detergent, and requiring not only excessive distillation but also a good deal of tank storage capacity.

Another object of the invention, therefore, is to provide an improved dry cleaning system and method which accomplish high quality cleaning by the use of suitably high detergent concentration, while at the same time resulting in low soap residue in the fabric, low soap consumption, and eliminating any necessity for the use of ex cessive quantities of solvent.

Another object is to provide a system which permits use of a combined extractor-washer (in itself economical and eificient) which allows extraction of the filtered soap liquor to a point where very little of the detergent and soluble soil is carried over into the rinse bath, thereby requiring a comparatively small quantity of solvent in the rinse supply, but still maintaining over a long period the comparative purity of that bath. The soap, being in one bath only is not lost so rapidly through distillation, since only a small proportion of the soap bath requires distillation as compared to the rinse bath.

Still another object is to provide an improved system in which separate baths and filters make possible the use of different types of filter aid, one for the soap bath and one for the rinse bath. Thus, the rinse filter conveniently may include a sweetenin agent, such as activated clay, without any effect upon the detergent used in the Wash bath and the latter bath preferably may be filtered by the use of diatomaceous earth.

Another object is to provide an improved dry cleaning system, with two baths, making it possible to maintain a much lower concentration of soluble soil in the rinse solvent than is the case in a single bath system.

Finally, another object is to eliminate the use of a separate extractor and provide a system which is adaptable for use with either one or two washer-extractors, thereby in either case utilizing both continuously operating filters to full advantage.

Further objects of the invention in part are obvious and in part will appear more in detail hereinafter.

In the drawings, the single view illustrates more or less conventionally, in diagrammatic form, one arrangement of dry cleaning system embodying the invention.

While the drawing illustrates two washerextractors coupled or connected in parallel for alternate use, the piping and valves are of such form and arrangement that the same view of the drawing conveniently may be employed for the description of the operation of a system embodying but one unit or washer-extractor. This will be described first.

Of course, in the consideration of the various steps or cycles of operation it is not essential that the various valves or other controlling devices be operated by an automatic control mechanism or system. However, such automatic control is preferable, and, in practice, the apparatus or system is entirely automatic, requiring only to be started when the washer-extractor has been loaded and closed. To symbolize such automatic operation certain valves are shown with a rectangular cap, representing a fluid-operated servomotor for each. With a single washer-extractor, seven such valves are necessary; a two washer system requires five extra valves.

The dry cleaning system shown includes a rinse bath tank I, soap bath tank 2, wash makeup tank 3, wash bath filter aid slurry tank 4, rinse bath filter aid slurry tank 5, pumps 6, I, wash filter Ill, rinse filter H, combined washerextractor 34, and various pipes, valves and other devices later to be referred to. Washer-extractor 34 may be any machine including a foraminous work holding drum rotatable at low speed for Washing and at high speed for extractor.

One cycle of operation and flow for a single washer-extractor system is as follows:

Assuming that the washer-extractor has been loaded with garments or fabrics to be cleaned, and that all parts are ready for operation, but in the shut down stage or condition, rinse tank I and soap bath tank 2 are first filled with a suitable solvent liquid to level A. The liquid, for example, may be a petroleum solvent.

This solvent is supplied from tank 49 by pump 52 and pipe 55 through hand valve 5| to rinse make-up tank 48, and by hand valve H to wash make-up tank 37 Valve 44 being open, as will later appear, the liquid flows through pipe 45 to tank 2 until it is filled to the minimum level C, which thereafter is maintained automatically, as will later appear.

Pumps 6 and l are started, with valves 8, 9 open and the washer inlet valves 35, 54 closed. Thisfills filters Ill, II, with further supply of solvent to tanks l and 2, to maintain the minimum level C.

Levels of liquid, as well as sizes of washers, tanks, filters, etc., are diagrammatic only, not to scale.

Solvent now circulates from soap bath tank 2 by pipe I2, pump 5, pipe I3, filter I5, pipe I4, pipe I5, and valve 8, back to tank 2.

Similar flow occurs from rinse tank I, by pipe I6, pump I, pipe I1, filter II, pipe l8, pipe I9 and valve Qback to tank I.

Filter aid is fed from wash filter aid slurry tank 4 by way of pipe 25 and check valves 2|, 22 into pipe I3 and into the bottom of the filter, being injected thereinto by diaphragm pump 23 in controlled impulses by means of air operated servomotor 24. Being injected on the discharge side of pump 6, the filter aid does not traverse said pump, but is fed directly into filter I9, where a precoat is formed upon the filter leaves.

A ,solvent supply pipe 25, controlled by valve 26, runs from pipe I4 to slurry tank 4.

In a similar way filter II is charged with its appropriate filter aid from rinse bath filter aid slurry tank 5, through pipe 27, check valves 28, 29, pipe H, the diaphragm pump 35, air operated servomotor 3I, supply pipe 32, and valve 33 functioning in the same manner as the corresponding parts in the soap bath circuit before described.

Pumps 6 and u now continue their operation during all subsequent steps or cycles of operation.

Valve 8 is now closed and valves 35 and 35 are opened. Valves 53, 5d and 55 remain closed.

The soap bath or wash liquor now circulates from tank 2 by way of pipe l2, pump 5, pipe I3, filter I0, pipe I l, pipe 3? and valve 35 into the top of washer 34, wherein the level of liquid rises until it reaches that of overflow pipe 38 on button trap 35, which completes a full liquid charge for the system. Flow continues through washer drain pipe 45, trap 35, pipe 38, valve 35 and pipe 4| back to tank 2. The washing cylinder rotates at washng speed, while the heavily doped wash bath, continuously filtered, circulates through the washer and the load of work therein.

As the Washer fills to the working level, during the operation of charging an empty system, wash liquor flows into tank 2 from supply pipe 55 to maintain the minimum level C. This minimum working level is maintained automatically by any suitable means here indicated diagrammatically as an air-actuated bellows 42 operating switch 43 in an electric circuit from leads LI, L2, and including a solenoid operated valve 44 in pipe 55 leading from tank 3 to tank 2. This valve automatically governs the admittance of make-up liquor to tank 2. An air supply pipe 56 effective upon the bellows has its discharge end submerged in the liquid in tank 2. The back pressure in this pipe varies with the head of liquid and its consequent level in tank 2. The adjustment (such as of the load spring on the bellows) is such that as a lowering level approaches level C, the back pressure in air line 46 drops enough to allow bellows 42 to retract, closing switch .3, and through the circuit from LI to L2 actuating valve 54 to open it. Make-up liquor then flows to tank 2 until restoration of the minimum level expands bellows 42 and actuates switch 53 and valve 55 in the opposite direction, cutting off the flow.

The level control for rinse liquor tank I is similar and requires no separate description.

While the soap bath or washing cycle proceeds, the rinse bath circulates continuously through its washer by-pass circuit already referred to.

At the conclusion of the washing or cleaning cycle, valve 35 closes and valves 8 and 53 open. This puts the by-pass circuit for the soap bath back into operation, cuts off the supply of soap bath to the top of the washer, and allows the washer and trap 39 to drain throughvalve 53, pipe 38, valve 35, and pipe M into tank 2, in which the liquid level rises above level C.

The Work container is now brought up to extracting speed and after the required extracting period, it is braked to low speed, the valves remaining unchanged in their washer draining positions. The rinse cycle now begins.

Valves 36, 53 and 9 close, while valves 55 and 55 open. This causes the rinse bath to circulate from tank I through pipe 56, pump a, pipe ll, rinse filter II, pipe I8, and valve 54 into the top of the washer, out through pipe 55, overflow trap 39, pipe 38, valve 55, and pipes 55, 5? back to tank I. Closing of valve 3 has cut ofi the rinse by-pass circuit. The wash by-pass circuit however, is open and continues to operate, further filtering that bath.

When the required rinsing has been accomplished, valve 54 closes, cutting ofi flow of rinse liquor into the washer, and valves 9 and 53 open, thereby re-establishing the rinse by-pass circuit and allowing the washer and trap 35 to drain the rinse bath through valve 53, pipe 38, valve 55 and pipes 56, 51 to tank I.

When the washer is completely drained, the container again is brought up to extracting speed and the extracted solvent drains in the same way, after which the container is stopped and unloaded.

Both the wash and rinse bath now continue to circulate through their respective filter and bypass circuits.

Succinctly stated, the operation consists in continuously maintaining a circuit and flow of the two baths, each through its own filter, at all times, and at intervals, and alternately, sendmg each bath through the washer while the other continues through its by-pass. Extracting occurs after both washing and rinsing, while both baths are by-passed.

One important feature of the invention is a thorough extraction of the maximum quantity of wash liquor from the work before rinse bath is supplied to it. This reduces to a very low value the usual contamination of the following rinse bath by soap and soluble soil, even though the soap bath is of high soap concentration.

' When two Washer-extractors are employed, the second, marked 58, is connected in the system in the manner shown, in parallel, as it were,

, with the first, five extra valves 59, 63, 64, 65 and 61 and their respective pipes being employed for the purpose.

Assuming that washer 34 is working on the soap bath, washer 5B of course will be working on the rinse bath, and vice versa.

While direct and exact alternation from one to the other bath may not be entirely satisfactory from all standpoints, on account of variations in washing and rinsing times for various loads or materials, or periods of loading and unloading, etc., the use of two washer-extractors, coupled as shown, by appropriate staggering of loads, considerably reduces the time during which either of the filters operates unpro- I ductively on by-pass.

In a two washer system, when washer 34 is on its washing cycle and washer 58 on rinse, the flow may be traced as follows:

Soap liquor flows from tank 2 through pipe I2, pump 6, pipe I3, filter I0, pipes I4 and 31, valve 35, washer 34, drain pipe 40, trap 39, pipe 38, valve 36 and pipe 4I back to tank 2. Rinse solvent is flowing from tank I through pipe I6, pump I, pipe I'I, filter II, pipe I3 and valve 59 into washer 58, then through pipe 66, trap 6|, pipe 62, valve 63 and pipe 51 back to tank I. During this period valves 54 and 64 at the washer inlets are closed and valves 55 and 65 below the traps 39 and 6| are closed,

thus preventing mixing of the two bath-s.

When one or the other of the washers completes its particular operation (washing or rinsing), this bath is put on by-pass and the washer is drained and operated as an extractor, after which the bath is switched over to the other washer, if the latter is ready for the next bath.

In the case being traced, that means that washer 34, for example, would now be ready for the rinse, and washer 58, having been unloaded and reloaded, would be ready for the soap bath.

Inlet valves 35 and 59 therefore would be closed and inlet valves 54 and 64 opened, 0 that the soap bath supply through pipe I4 now goes over to washer 58 through valve 64, while the rinse bath goes across to washer 34 through its valve 54.

Similarly, beyond the overflows, the rinse solvent from washer 34 flows through pipe 38, valve 55 and pipes 56, 5'! back to rinse tank I; while the soap liquor from washer 58 flows through pipe 62, valve 65 and pipes 66, 4| back to soap tank 2.

In this case, inlet valves 35 and 59 on the washer inlets are closed and valves 36 and 63 beyond the overflows are closed, again to prevent mixing of the baths.

The respective by-pass valves 8, 9 and drain valves 53, 67, operate at the end of each period in the usual way, the two baths each draining into their appropriate tanks.

It will therefore be observed that in this system, whether operating with one or more washer-extractors, two baths, one for washing and the other for rinsing, are continuously circulated independently of each other, each from is own supply tank through it pump and filter and back again to its own tank. During draining, extracting, unloading and loading both baths are by-passed around and do not go through the washer. But at all times, continuously and without interruption each bath is circulated through its own filter, in which the filter leaves, coated with the particular filter aid suitable for the bath, separate, hold back and collect foreign matter removed from the work undergoing treatment.

When a single washer-extractor is employed washing and rinsing cycles succeed each other, the intervening periods being employed for draining, extracting, unloading and loading. When two washers are used, the same succeeding cycles occur, but alternately or in staggered relation, first in one and then in the other. In other words, only two baths, washing and rinsing are required for two or more washer-extractors.

In all arrangements, thorough extraction intervenes between washing and rinsing and reduces contamination of either bath by the other.

Level C, in tanks I and 2, is the minimum level which is always maintained automaticallly by control pipe 46 when the system is in operation. The solvent is at this level when the washer and the filter are both filled.

Level A is that which occurs when the pumps 6, I are stopped and the washer-extractors and filters are permitted to drain.

' Level B is the working level of liquid when pumps 6, I and filters I6, II are in operation, and the washer-extractor is empty.

The system as a whole is relatively simple, saves time in operation, reduces the cost for soap, detergents and solvent liquors, and is highly efficient in operation.

Other advantages of the invention will be apparent to those skilled in the art,

What I claim is:

1. Fabric cleaning apparatus comprising a washing machine, a supply of washing liquid, 2. supply of rinsing liquid, a washing liquid filter, a rinsing liquid filter, a washing liquid inlet conduit between said washing liquid filter and said washing machine, a rinsing liquid inlet conduit between said rinsing liquid filter and said washing machine, a washing liquid drain return channel between the washing machine and the inlet side of the washing liquid filter, a rinsing liquid drain return channel between the washing machine and the inlet side of the rinsing liquid filter, a washing liquid by-pass channel from the outlet side of the washing liquid filter to the inlet side thereof, a rinsing liquid by-pass channel from the outlet side of the rinsing liquid filter to the inlet side thereof, a washing liquid pump in continuous liquid flow communication with the inlet side of the washing machine filter, and a rinsing liquid pump in continuous liquid flow communication with the inlet side of the rinsing liquid filter.

2. Fabric cleaning apparatus comprising a washing machine, a supply of washing liquid, a supply of rinsing liquid, a washing liquid filter, a rinsing liquid filter, a washing liquid inlet conduit between said washing liquid filter and said washing machine, a rinsing liquid inlet conduit between said rinsing liquid filter and said washing machine, a washing liquid drain return channel between the washing machine and the inlet side of the washing liquid filter, a rinsing liquid drain return channel between the washing machine and the inlet side of the rinsing liquid filter, a washing liquid by-pass channel from the outlet side of the washing liquid filter to the inlet side thereof, a rinsing liquid by-pass channel from the outlet side of the rinsing liquid filter to the inlet side thereof, a washing liquid pump in continuous liquid fiow communication with the inlet side of the washing machine filter, a rinsing liquid pump in continuous liquid flow communication with the inlet side of the rinsing liquid filter, and flow-controlling means for diverting liquid fiow from each pump either through its respective by-pass channel or through the washing machine.

3. Fabric cleaning apparatus comprising a washing machine, a supply of washing liquid, a supply of rinsing liquid, a washing liquid filter, a rinsing liquid filter, a washing liquid inlet conduit between said washing liquid filter and said washing machine, a rinsing liquid inlet conduit between said rinsing liquid filter and said washing machine, a washing liquid drain return channel between the washing machine and the inlet side of the washing liquid filter, a rinsing liquid drain return channel between the washing machine and the inlet side of the rinsing liquid filter, a washing liquid by-pass channel from the outlet side of the washing liquid filter to the inlet side thereof, a rinsing liquid by-pass channel from the outlet side of the rinsing liquid filter to the inlet side thereof, a washing liquid pump in continuous liquid flow communication with the inlet side of the washing machine filter, a rinsing liquid pump in continuous liquid flow communication with the inlet side of the rinsing liquid filter, and flow impeding means in each by-pass channel for diverting the liquid output of its respective pump either through its respective by-pass channel or through the washing machine.

4. Fabric cleaning apparatus comprising a washer-extractor machine, a supply of washing liquid, a supply of rinsing liquid, a washing liquid filter, a rinsing liquid filter, a washing liquid inlet conduit between said washing liquid filter and said washer-extractor machine, a rinsing liquid inlet conduit between said rinsing liquid filter and said washer-extractor machine, a washing liquid drain return channel between the washerextractor machine and the inlet side of the washing liquid filter, a rinsing liquid drain return channel between the washer-extractor machine and the inlet side of the rinsing liquid filter, a washing liquid by-pass channel from the outlet side of the washing liquid filter to the inlet side thereof, a rinsing liquid by-pass channel from the outlet side of the rinsing liquid, filter to the inlet side thereof, a washing liquid pump in continuous liquid flow communication with the inlet side of the washing liquid filter, a rinsing liquid pump in continuous liquid flow communication with the inlet side of the rinsing liquid filter, and valve means in each by-pass channel for diverting the liquid output of its respective pump either through its respective by-pass channel or through the washer-extractor machine.

5. Fabric cleaning apparatus comprising a washing machine, a supply of washing liquid, a supply of rinsing liquid, a washing liquid filter, a rinsing liquid filter, a washing liquid inlet conduit between said washing liquid filter and said washing machine, a rinsing liquid inlet conduit between said rinsing liquid filter and said washing machine, a washing liquid drain return channel between the washing machine and the inlet side of the washing liquid filter, a washing liquid reservoir in said washing liquid drain return channel, a rinsing liquid drain return channel between the washing machine and the inlet side of the rinsing liquid filter, a rinsing liquid reservoir in said rinsing liquid drain return channel, a washing liquid by-pass channel from the outlet side of the washing liquid filter to the washing liquid reservoir, a rinsing liquid by-pass channel from the outlet side of the rinsing liquid filter to the rinsing liquid reservoir, a washing liquid pump in continuous liquid flow communication between the inlet side of the washing machine filter and the washing liquid reservoir, a rinsing liquid pump in continuous liquid fiow communication between the inlet side of the rinsing liquid filter and the rinsing liquid reservoir, the washing liquid filter, conduit, and channel having a combined volumetric capacity sufficient to contain the washing liquid supply, and the rinsing liquid filter, conduit, and channel having a combined capacity sufficient to contain the rinsing liquid supply.

6. Fabric cleaning apparatus comprising a washing machine, a supply of washing liquid, a supply of rinsing liquid, a washing liquid filter, a rinsing liquid filter, a washing liquid inlet conduit between said washing liquid filter and said washing machine, a rinsing liquid inlet conduit between said rinsing liquid filter and said washing machine, a washing liquid drain return channel between the washing machine and the inlet side of the washing liquid filter, a washing liquid reservoir in said washing liquid drain return channel, a rinsing liquid drain return channel between the washing machine and the inlet side of the rinsing liquid filter, a rinsing liquid reservoir in said rinsing liquid drain return channel, a washing liquid by-pass channel from the outlet side of the washing liquid filter to the inlet side thereof, a rinsing liquid by-pass channel from the outlet side of the rinsing liquid filter to the inlet side thereof, a washing liquid pump in continuous liquid flow communication between the inlet side of the washing machine filter and the washing liquid reservoir, a rinsing liquid pump in continuous liquid flow communication between the inlet side of the rinsing liquid filter and the rinsing liquid reservoir, valve means for directing washing liquid flow either through said washing liquid filter and said washing liquid by-pass channel or through said washing liquid filter and said washing machine, and additional valve means for directing rinsing liquid flow either through said rinsing liquid filter and said rinsing liquid by-pass channel or through said rinsing liquid filter and said washing machine.

'7. Fabric cleaning apparatus comprising a washer-extractor machine, a washing liquid filter, washing liquid inlet piping extending from the outlet side of the washing liquid filter to the inlet side of the washer-extractor machine, washing liquid return means between the outlet from the washer-extractor machine and the inlet side of the washing liquid filter, washing liquid bypass piping extending from said washing liquid inlet piping to said washing liquid return means, a first valve in said washing liquid inlet piping between said by-pass pip-ing and the inlet to said washing machine, a second valve in said Washing liquid return means between said by-pass piping and the outlet from said washer-extractor machine, a rinsing liquid filter, rinsing liquid inlet piping extending from the outlet side of the rinsing liquid filter to the inlet to said washer-extractor machine, rinsing liquid return means between the outlet from said washer-extractor machine and the inlet side of said rinsing liquid filter, rinsing liquid by-pass piping extending from said rinsing liquid inlet piping to said rinsing liquid return means, a third valve in said rinsing liquid inlet piping between the rinsing liquid by-pass piping and the inlet to the Washer-extractor machine, a fourth valve in said rinsing liquid return means between the rinsing liquid by-pass piping and the outlet from said washer-extractor machine, a continuously operatable washing liquid pump in liquid flow communication with said washer-extractor machine and said filter when said first and second valves are open, a continuously operatable rinsing liquid pump in continuous liquid flow communication with said rinsing liquid filter and with said washer-extractor machine when said third and fourth valves are open.

8. Fabric cleaning apparatus comprising a washing machine, a washing liquid filter, washing liquid inlet piping extending from the outlet side of the washing liquid filter to the inlet side of the washing machine, washing liquid return means between the outlet from the washing machine and the inlet side of the washing liquid filter, washing liquid by-pass piping extending from said washing liquid inlet piping to said washing liquid return means, a first valve in said washing liquid inlet piping between said by-pass piping and the inlet to said washing machine, a second valve in said washing liquid return means between said by-pass piping and the outlet from said washing machine, a rinsing liquid filter, rinsing liquid inlet piping extending from the outlet side of the rinsing liquid filter to the inlet to said washing machine, rinsing liquid return means between the outlet from said washing machine and the inlet side of said rinsing liquid filter, rinsing liquid by-pass piping extending from said rinsing liquid inlet piping to said rinsing liquid return means, a third valve in said rinsing liquid inlet piping between the rinsing liquid by-pass piping and the inlet to the washing machine, a fourth valve in said rinsing liquid return means between the rinsing liquid by-pass piping and the outlet from said washing machine, a continuously operatable washing liquid pump in liquid flow communication with said washing machine and said filter when said first and second valves are open, a continuously operatable rinsing liquid pump in continuous liquid flow communication with said rinsing liquid filter and with said Washing machine when said third and fourth valves are open, means for preventing washing liquid flow in said washing liquid by-pass piping when said first and second valves are open, and means for preventing rinsing liquid flow in said rinsing liquid by-pass piping when said third and fourth valves are open.

9. Fabric cleaning apparatus comprising a washing machine, a washing liquid filter, washing liquid inlet piping extending from the outlet side of the washing liquid filter to the inlet side of the washing machine, washing liquid return means between the outlet from the washing machine and the inlet side of the washing liquid filter, washing liquid by-pass piping extending from said washing liquid inlet piping to said washing liquid return means, a first valve in said washing liquid inlet piping between said by-pass piping and the inlet to said washing machine, a second valve in said washing liquid return means between said by-pass piping and the outlet from said washing machine, a rinsing liquid filter, rinsing liquid inlet piping extending from the outlet side of the rinsing liquid filter to the inlet to said washing machine, rinsing liquid return means between the outlet from said washing machine and the inlet side of said rinsing liquid filter, rinsing liquid by-pass piping extending from said rinsing liquid inlet piping to said rinsing liquid return means, a third valve in said rinsing liquid inlet piping between the rinsing liquid by-pass piping and the inlet to the washing machine, a fourth valve in said rinsing liquid return means between the rinsing liquid by-pass piping and the outlet from said washing machine, a continuously operatabl washing liquid pump in liquid fiow communication with said washing machine and said filter when said first and second valves are open, a continuously operatable rinsing liquid pump in continuous liquid fiow communication with said rinsing liquid filter and with said washing machine whien said third and fourth valves are open, a fifth valve in said washing liquid by-pass piping for preventing liquid flow in said washing liquid by-pass piping when said first and second valves are open, and a sixth valve in said rinsing liquid by-pass piping for preventing liquid flow in said rinsing liquid by-pass piping when said third and fourth valves are open.

10. Fabric cleaning apparatus comprising a washing machine, a washing liquid filter, washing liquid inlet piping extending from the outlet side of the washing liquid filter to the inlet side of the washing machine, washing liquid return means between the outlet from the washing machine and the inlet side of the washing liquid filter, Washing liquid by-pass piping extending from said washing liquid inlet piping to said washing liquid return means, a first valve in said washing liquid inlet piping between said by-pass piping and the inlet to said washing machine, a second valve in said Washing liquid return means between said by-pass piping and the outlet from said washing machine, a rinsing liquid filter, rinsing liquid inlet piping extending from the outlet side of the rinsing liquid filter to the inlet to said washing machine, rinsing liquid return means be tween the outlet from said washing machine and the inlet side of said rinsing liquid filter, rinsing liquid by-pass piping extending from said rinsing liquid inlet piping to said rinsing liquid return means, a third valve in said rinsing liquid inlet piping between the rinsing liquid by-pass piping and the inlet to the washing machine, a fourth valve in said rinsing liquid return means between the rinsing liquid b-y-pass piping and the outlet from said washing machine, a continuously operatable washing liquid pump in liquid flow communication with said washing machine and said filter when said first and second valves are open, a continuously operatable rinsing liquid pump in continuous liquid flow communication with said rinsing liquid filter and with said washing machine when said third and fourth valves are open, fiow impeding means in said washing liquid by-pass for preventing washing liquid flow therethrough when said first and second valves are open, and flow impeding means in said rinsing liquid by-pass piping for preventing rinsing liquid flow therethrough when said third and fourth valves are open.

11. Fabric cleaning apparatus comprising a Washing machine, a supply of washing liquid, a supply of rinsing liquid, a washing liquid filter, a rinsing liquid filter, a washing liquid inlet conduit between said washing liquid filter and said washing machine, a rinsing liquid inlet conduit between said rinsing liquid filter and said Washing machine, a washing liquid drain return channel between the washing machine and the inlet side of th washing liquid filter, a Washing liquid reservoir in said drain return channel, a rinsing liquid drain return channel between the washing machine and the inlet side of the rinsing liquid filter, a rinsing liquid reservoir in said rinsing liquid drain return channel, a washing liquid by-pass channel from the outlet side of the washing liquid filter to the inlet side thereof, a rinsing liquid by-pass channel from the outlet side of the rinsing liquid filter to the inlet side thereof, a washing liquid pump in continuous liquid fiow communication between the inlet side of the washing liquid filter and the washing liquid reservoir, a rinsing liquid pump in continuous liquid flow communication between the inlet side of the rinsing liquid filter and the rinsing liquid reservoir, and flow controlling means for diverting liquid flow from each pump either through its respective b y-pass channel or through the washing machine.

12. Fabric cleaning apparatus comprising a Washer-extractor machine, a washing liquid filter, washing liquid inlet piping extending from the outlet side of the washing liquid filter to the inlet side of the washer-extractor machine, washing liquid return means between the outlet from the washer-extractor machine and the inlet side or the washing liquid filter, a washing liquid reservoir in said washing liquid return means, washing liquid by-pass piping extending from said washing liquid inlet piping to said washing liquid return means, a first valve in said washing liquid inletpiping between said by-pass piping and the inlet to said washer-extractor machine, 'a. second valve in said washing liquid return means between the outlet from said washing machine and said washing liquid reservoir, a rinsing liquid filter, rinsing liquid inlet piping extending from the outlet side of the rinsing liquid filter to the inlet to said Washer-extractor machine, rinsing liquid return means between the outlet 12 from said washer-extractor and the inlet side of said rinsing liquid filter, a rinsing liquid reservoir in said rinsing liquid return means, rinsing liquid by-pass piping extending from said rinsing liquid inlet piping to said rinsing liquid return means, a third valve in said rinsing liquid inlet piping between the rinsing liquid by-pass piping and the inlet to the washer-extractor machine, a fourth valve in said rinsing liquid return means between the outlet from said washer-extractor and said rinsing liquid reservoir, a continuously operatable washing liquid pump in liquid flow communication between said washing liquid reservoir and said filter, a continuously operatable rinse liquid pump in continuous liquid flow communication between said rinsing liquid reservoir and said filter, a fifth valve in said washing liquid by-pass piping for preventing liquid flow in said washing liquid by-pass piping when said first and second valves are open, and a sixth valve in said rinsing liquid by-pass piping for preventing liquid flow in said rinsing liquid by-pass piping when said third and fourth valves are open.

EDWARD A. CRESWICK.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 888,576 Bartholomew May 26, 1908 2,087,775 Matthews July 20, 1937 2,130,817 Shaw Sept. 20, 1938 2,273,170 Baron Feb. 17, 1942 2,302,923 Zimarik Nov. 24, 1942 2,305,154 Gilbert Dec. 15, 1942 2,307,254 Basse'tt Jan. 5, 194-3 2,554,566 Geldhof et al. May 29, 1951 FOREIGN PATENTS Number Country Date 426,019 Great Britain Mar. 26, 1935 

